Autofill email addresses (e.g., for log ins) on mobile Safari will not let me pick my email

I have 8 email addresses in my Contacts app, most i never use. The AutoFill email address (in mobile safari) options I am given have no rhyme or reason. Just now, on one website, the only Autofill options were to enter in a Hide My Email (fine, great!) and one of my email addresses I NEVER use. There is no option to select one of my 7 other email addresses listed in my personal Contact card. There appears no way to select a default email address. Frustrating just because it defeats the purpose of autofill. I just tried to sign in to CVS.com, and the options from autofill are either HideMyEmail or one of 4 alias emails I have. And the alias it chose is one I NEVER use.